Post Ajax submission of jquery in [laravel5.4]

1. The ajax of the post needs to submit the csrf_token field for security filtering

<meta name="csrf-token" content="{{ csrf_token() }}">
/* ajax backfills the form fields, then submits the form */
                $.ajax({
                    headers: {
                        'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
                    },
                    type: 'POST',
                    url: '/ddoa/***',
                    data: {event:'crm_user',ding_name:ding_name,ding_userid:ding_userid,ding_openId:ding_openId},
                    dataType: 'json',
                    async : 'false', //sync
                    success: function(data){
                        logger.i(data);
                        console.log(data);
                        if(data.code==1){
                            $("input[name='username']").val(data.username);
                            $("input[name='password']").val('123456');
                            $("#loginForm").submit();
                        }
                       },
                       error:function(data){
                        console.log(data);
                       }
                });